If you use a different material for supports like PETG, you can basically set the top Z distance to 0 in most cases, this results in a significantly better surface quality at the supported face. Also, as already mentioned, the purge tower reduces/prevents the discolorations, on the cost of longer print-times and more material waste. In your example this might lead to the PETG-layer stick to the surface when you remove the supports, but it should still be easy to remove since it doesn't bond with the PLA. While the AMS is very convenient, I still try to minimize material-changes, since they take a lot of time and produce a lot of waste. Thus, I also try to design parts in a way that as little supports are needed as possible. A function that I miss in the orca-slicer is to change the time when materials get changed. When I use PETG for support-faces, let's say for 2 Layers, it always prints the supports first and the part second. It would make much more sense if it would print the part first at the first layer where the PETG is used, then switch to the PETG, print the supports for this layer, go up to the next layer, print the supports for that and only then change back to the normal material to print the part. This would cut the material changes by half...

A few things to know, when using an interface layer with a different material, make sure to have a significant flush on the filament change. That line of darker material you see is PETG in your PLA, which will make that part extremely weak (generally). Good choice not to use a purge tower, as I find they often fall apart when using different materials. Also, note that was a perfect test subject for the PETG interface. Other shapes will be significantly more troublesome. I found anything more than a flat single layer ( or 2 layer) interface was more tricky. Meaning, geometry that makes the interface curve from one height to another are highly problematic. The final thing I liked was no air gap when using different materials. Also, I like using a larger XY air gap. I believe the default it .35mm but I generally go to .50 to 1.00mm. This really helps with removal for the same material support with very little quality issues. But note that some geometry will have issues with too much XY gap.

I get a cleaner print if the interface z distance is 0mm. (when using dissimilar material)

Another awesome video. Thank you. Do you have a text video? Do you know how to curve text to a circular pattern? I cant seem to figure it out.

Hey! Brand new to this, I was wondering how we can set the z-offset in orca?

I wish you addressed the seam scarf feature because there is information out there with different settings. I use 100% seam gap and contour with no seam.

Thanks for your video. I'm about to do a big print in PETG with the top surface facing down in contact with the support to reduce time by half. It seems by looking at your video that orca slicer does not provide miracles in its settings. Since I print in PETG I was wondering if the PETG CF was maybe a better choice in this regard to leave a nicer surface finish once support removed. Any idea? Also , Is there any way to set ironing on the layer just after last support layer ?

If possible to use .8 Nozzle. I have Ender 3 V2 printer